This invention relates generally to the field of medical instruments, and more particularly relates to an electrocautery device.
Various types of electrocautery devices for incising and cauterizing body tissue are known and used in the medical field. Typically, such devices include a conductive blade or needle which serves as one electrode in an electrical circuit which is completed via a grounding electrode coupled to the patient. Incision of tissue is accomplished by applying a source of electrical energy (most commonly, a radio-frequency generator) to the blade. Upon application of the blade to the tissue, a voltage gradient is created, thereby inducing current flow and related heat generation at the point of contact. With sufficiently high levels of electrical energy, the heat generated is sufficient to cut the tissue and, advantageously, to simultaneously cauterize severed blood vessels.
It is widely recognized in the prior art that the often substantial amount of smoke produced by electrocauterization of tissue is at least unpleasant, and in some cases distracting or even hazardous to the operator and other attending medical personnel. As a result, it has been proposed, and is common, to provide an electrocautery device with smoke-aspirating capabilities, such that the smoke produced from electrocauterization is quickly withdrawn from the area of incision. Smoke aspiration may be accomplished by providing, in the handle of the electrocautery device near the electrocautery blade/electrode, an inlet port to be coupled to a vacuum or suction source. Examples of this are described in U.S. Pat. No. 4,307,720 to Weber, Jr., entitled xe2x80x9cElectrocautery Apparatus and Method and Means for Cleaning the Same;xe2x80x9d in U.S. Pat. No. 5,242,442 to Hirschfeld, entitled xe2x80x9cSmoke Aspirating Electrosurgical Device;xe2x80x9d and in U.S. Pat. No. 5,269,781 to Hewell, entitled xe2x80x9cSuction Assisted Electrocautery Unit.xe2x80x9d
It has also been recognized in the prior art that the accumulation of coagulated blood, tissue rubble, and other debris on the electrode/blade of an electrocautery device can present a problem for the operator, necessitating the periodic cleaning of the blade, e.g., by wiping the blade over sterilized gauze or the like. This is, generally regarded as undesirable, since the need to clean the electrode/blade tends to interrupt the incision procedure and increases the risks associated with contamination of the blade or the incision, damage to the blade, injury to the operator, and the like. To address this problem, it has been proposed in the prior art to provide an electrocautery instrument in which the electrode/blade is in slidable engagement with the instrument""s handle, such that when the blade is retracted into the hand, any adhering debris automatically scraped off onto the tip of the handle. Such an instrument is proposed in the above-referenced Weber, Jr. ""720 patent. While this arrangement may have some benefit, it still may be necessary to wipe off the tip of the handle once the blade is retracted. It is believed that a more direct and effective approach to the problem would be to reduce the amount of debris created during the electrocautery process, thereby eliminating or at least reducing the need to clean the electrode/blade.
In view of the foregoing considerations, the present invention is directed to an improved electrocautery instrument.
In one embodiment of the invention, an electrocautery instrument is configured with an electrode/blade disposed within a retractable suction tube, such that with the suction tube advanced, the electrode/blade is concealed within the tube, and with the suction tube retracted, the distal end of the electrode/blade is exposed for performing electrocautery.
In accordance with one aspect of the invention, the electrocautery electrode/blade is implemented with a hollow, conductive tube, flattened at it distal end into a blade-like configuration. Conductive fluid is applied to the proximal end of the hollow electrode/blade, and expelled from the distal (blade) end thereof during electrocautery. In accordance with another aspect of the invention, the conductive fluid emanating from the electrode/blade conducts the RF electrocautery energy away from the blade, so that it is primarily the fluid, rather than the metal blade, which actually accomplishes the cutting of tissue. That is, the fluid serves as a xe2x80x9cvirtualxe2x80x9d electrocautery electrode. Since it is the fluid, rather than the blade, which incises and cauterizes, no burns or perforations are made to the tissue, reducing the amount of debris in the incision. Also, the flow of fluid through the electrode/blade tends to keep the blade clean and cool.